The objective of this proposal is to synthesize some new gossypol derivatives for use as male contraceptives. The fact that gossypol, itself, is already being used as a male contraceptive agent in China, and the need for an inexpensive, reversible, non-toxic male contraceptive in developing countries indicates that new more potent gossypol derivatives will be commercially successful. The gossypol derivatives will be tested for ability to inhibit: 1) androgen and estrogen binding to proteins; 2) sperm motility; and 3) sperm metabolism. Also, we will prepare sufficient quantities of these analogues for later in vivo studies (phase II) with rats and hamsters. Also, later studies (phase II) may include testing these gossypol derivatives for ability to inhibit the growth of trypanosoma cruzi and killing herpes virus.